A170811 Number of permutations of 1..n with all differences of elements separated by distances 1 through 5 being respectively unique.

1, 2, 4, 12, 40, 116, 200, 444, 760, 2160, 4368, 7852, 14040, 24284, 42312, 79340, 152764, 320920, 688780, 1577244, 3763512, 9412948

Offset

1,2

Comments

(Empirical) Equals A008404 for n<=2m+2, where m is the maximum difference separation 5.

Links

Table of n, a(n) for n=1..22.

Crossrefs

Sequence in context: A170814 A170813 A170812 * A170810 A170809 A170808

Adjacent sequences: A170808 A170809 A170810 * A170812 A170813 A170814

Keyword

nonn

Author

R. H. Hardin Dec 02 2009

Status

approved